ARUP

These two 'old school' stunt engines show no problem with Marvel Mystery Oil. The Fox 29 hasn't been used in over 40 years except to be run for fun from time to time. It's not rusted or locked up in any way. The McCoy sure is pretty, has great compression and runs! I don't want any varnish in my CL engines and these require a lot of castor relative to modern engines. The Judson on this VW engine uses MMO for lubrication. The compressor vanes are phenolic and the bearings are smooth as silk.

SrTelemaster150

Why would a "gas engine" present more problems than an engine run on hygrosopic alcohol fuels? ARO is used in alcohol engines to prevent corrosion from moisture absorbed by the alcohol left in the case after use. I don't think that the small amount of alcohol in 10% ethanol pumpm gasl presents nearly as much problem as the up to 90% methanol in glow fuels.

In fact, I've never heard of ARO being recommended by chainsaw manufacturers. I've never used ARO in my Stihl chansaw or trimmer.

Some peolple make things a lot more complicated than neccessary.

TimBle

Well said!

I've nt run castor in any of my engines for the last few years. The only engines I woul run castor in is an old lapped piston engine where tolerance could be as wide as the Suez canal. (gross exaggeration.....)

But time and time again at the airfield and these forums supposed experts will enforce the castor rule for glow engines and will then use outdated (read from the 1960's) information on synthetic technology.base number
People will always claim their ARO is the best and nothing tops it even when most stuff branded as ARO is just straight run group I base oil with a smatttering of anti oxidant (and you're charged an arm and a leg because it will sure cancer too) and anti corrosion additive.

There are people here who know what they're talking about and some who sound like they know but will bully others into the way of thought. Thankfully some of those ugly people have left or maybe just lurk today. But its seems their legacy continues.
For ARO, ATF is great, sewing machine oil is great, hydraulic oil is great, engine oil is great, anything with a anti oxidant, a fairly good base number and anti corrosion additve is ideal.

Castor works but its not thebest lubricant around. Its revered at flying fields all over the world even by experienced people who should know better.
Maybe synthetic gets a bad rap because the number of people who understand it can be measured in the 1000's out of a global population of billions.

I'm not making this stff up because "someone who flies once told me". I think i'm in a position to speak with some authority because I'm a member of a few tribology and Lubricating engineers institutes and associations and accredited by them so I think I kow a little more than the average RCflyer dpoes about lubricants.I don't profess to know it all either. I know what I know and I know what I don't know and I don't know what I don't know but I have the tools to find out,......not just google.com.

A lot of arguement is backed up by "what i observe...." but no real scientific quantification of thsoe observations yet we're all supposed to lap up the observations as gospel truth because someone on the internet said so.

SrTelemaster150 seems to know what he's talking about and lubricants tests I run have shown castor to be inferior in many aspects of lubricant performance, especially in high performance engines.
I wrote up something for Andrew at Controlchat a couple of years ago and even there the same people argue about the superiority of castor in 4 stroke engines where the science shows the opposite.

use castor if you want to but don't hold a gun to someone elses head when they speak from a position of knowledge.
If you want the best lubes for your engines then the quality branded synthetic oil containing fuels are ideal.

As far as E10 being a corrosion promoter in a gasoline two stroke,.......maybe you want to lean that needle a little.. Even so, as mr telemaster rightly states, the small percentage of ethoH does nto present a corrosion problems in the fuel if its been stored properly. Get water into any fuel and you will corrode that engine and its bearings

Keep the good work mr telemaster

SrTelemaster150

Here are some pix of a high hours Saito engine that was run W/castor oil in the fuel.




Here are some pix of my Saito FA91S that had moderate hours on it. It was stored indoors in a closet for 15 years. I only use ARO (ATF) @ the end of the season but I do drain the tank & run all of the fuel out of the engine @ the end of a flying session. This engine has been run exclusively on 15% Cool Power fuel W 16% full synthetic oil.






After a quick wipe of the thumb on the piston crown it looked like this.


The rear bearing after 15 tears of storage.


The only reason the engine was torn down was due to a crash straight in @ WOT from 30' altitude damaged the front bearing.

From my experience, synthetic oil does just as well as castor oil from a corrosion prevention standpoint even when ARO is not used @ the end of every flying session. Synthetic oil does not leave nearly as much harmful carbon and varnish as castor oil.

raptureboy

More popcorn!This really getting good

SrTelemaster150

Oops my bad!

hairy46

My Feedback: (1)

Marvel airtool oil is great!

TimBle

thats pretty much how clean y OS FS70 SII has been inside without any ARO and 10% Coolpower after 18months of storage.
I find claims that the build up of residue seen in the w/castor pics is somehow argued to be "advantageous".
But each to their own

1QwkSport2.5r

I have to admit those pictures above look pretty compelling. My Enya 60-4C has been run on 20% castor since new and the innards look nothing like that. Some slight carbon buildup on the exhaust valve, but otherwise clean. Very interesting indeed.

TimBle

How was the engine run? light duty, heavy duty?

toolmaker7341

It must have been run on cheap un degumed castor. Been running straight castor for ever,never had anything looking like that,never replaced a bearing,scored a liner or used ARO. Running castor(Benol) in a highly modified snowmobile engine(275 hp 900cc) for whole seasons no build up or cylinder scoring. If synthetics work for you great they don't work for me.

TimBle

un-de-gummed?

MTK

Well....degummed castor is the good stuff like benol. Un-degummed is the bad stuff.....the stuff that still has the gums in. Hell itprobably has its teeth too. Now I know what scores engine liners and pistons....it's the teeth

TimBle

or maybe the tartar on the teeth

Jim Thomerson

I use Rislone for long term storage. Regular MMO is OK short term. I like the smell. However, because it smells, doesn't that suggest it has a volatile component which will evaporate over time? I have seen engines stored long term with regular MMO which had hard red crud inside.

jessiej

Nothing beats sperm oil.

Jess

TimBle

I guess the source for that would be a mass debate on castor....






See what I did there

iskandar taib

My Feedback: (5)

From what I can find online, there is no such thing as undegummed castor. Degumming is the first thing they subject raw castor oil to, they treat it with hot water and steam. This removes proteins and gums.

Iskandar

ARUP

Castor oil and synthetic mix are probably a good compromise for us lazy modelers. Castor oil protects against lean runs. Castor has a higher flash point and actually has increasing lubricity with increasing temperatures... up to a point. Synthetics have very low flash points so one lean run (as in the end of a CL airplane's tank) causes more damage than one using castor. The best Fox 35 stunt engine is one just before it throws a rod.. cumulative end of tank lean runs! In my experience, Saito type engines (AAC) seem to be the most susceptible to damage from lean runs. Castor will leave deposits (varnish, etc.) in time so regular cleaning (disassembly) is in order. Synthetics maintain a clean engine. Just don't run engines with synthetic lubricants lean. You pays ur money- you takes ur chances!
Sorry for off topic response.

SrTelemaster150

The fact still remains that Saito (not Horizon) recommends agaist the use of any castor. Perhaps Horizon feels that American flyers are not to be trusted to tune their engines properly. Or perhaps Horizon is just pandering to American users that insist on using castor.

From the Saito spec's (fuel) pages.

The oil content recommended by Saito and Horizon Hobby is 20%. Horizon Hobby state that oil that is a blend of castor and synthetic is acceptable. Saito instructions (that no longer accompanies engines sold in the US) say the following: “Since the four-stroke engine has high exhaust temperature and carbon is apt to accumulate when castor oil type lubricants are used, avoid using fuel containing them.” This seems to imply Saito recommends fuel with no castor at all.


Something that I find puzzling is the suposedly higer temperatures burning off the synthetic lube.

That seems a bit odd since Saito (as well as Horizon) specify a full synthetic oil for the Saito FG gas engines that run much, much hotter than the glow versions.

My CDI fired FA150 ran more than 50 gllons of 15% Cool Power full synthetic lube fuel through the combustion chamber. CDI, even when igniting glow fuel, raises the CHT about 20°F over glow ignition W/the same fuel. Again, after all that time running @ elevated temperatures, there was no breakdown of the synthetic lube in my engines.

Lean runs on glow ignition result in detonation, not just elevated tempertures. Castor oil will not save your engine from detonation.

Jim Branaum

My Feedback: (3)

Well, no one has yelled at me this morning so lets change that!

I run Saito's and have had a bad experience with castor as my lube and shy away from it in any concentration over 5%. I went to a fly in almost 300 miles away and had to tear down my 120 in the middle of the day because it would not get over 6K rpm. The amount of sludge in all parts of that engine was impressive! I never was able to get that engine back up to 'spec' but I did not put new parts in it, just cleaned out the carbon and sludge.

After a little looking around, I concluded (not scientific - just observational) that many run their engines too rich which means there is excess lubricant that has to go somewhere. Too many set their needles as if they were running a 2 stroke and give away the top 2 or 3 % of engine power in addition to preventing the engine from reaching full internal operating temp, which contributes to the sludge build up.

Enough about oils in fuel, the subject here is after run stuff.

I worked my way through undergraduate school as a mechanic and am familiar with air tool oil. Being broke, I learned to use ATF. However, that is really only good if the unit is going to be used in the next few days. I don't like the results I had when I used that and let my tools set for a week.

However, I was talking to a friend who worked for a pipeline company and discovered they were using Rislone in their stand by pumps and had good results. So I bought my first quart some 20 years ago and have never had a bearing failure on an engine that was properly cared for.

In short, I have been impressed with the products protection of my engines and its fast departure when I go flying the next time. The first run is a bit smoky and low on the RPM's, but then it is gone and I am flying.

George Aldrich convinced me that 1/2 the battle with after run oils is properly caring for the engine, so I adopted most of his methods.

That 'properly cared for' bit is the 'secret' of success with many after run oils. Since my free time has always been in turmoil, I have always known that while I may PLAN to fly next week it is possible (and happened [] ) that it might not happen for 6 months or more.

So exactly what IS this "properly cared for"?

Simple, remove ALL the fuel from the engine by burning it off and then feed it after run oil of your choice - of course this is always done with the tank empty so fresh stuff is not sloshed into the carburetor. What is done, to both 2 and 4 strokes, is put the glow driver on the plug and set the throttle to idle and use the starter. When the engine starts, leave the driver in place and quickly give the engine help with the starter when it quits. When there is no evidence of further combustion, you are ready to remove the driver and feed the engine some after run oil.

I use 2 to 5 cc's in the carburetor of 2 strokes and about 1 or 2 inches in the vent tube of my 4 strokes. I put fuel line on the vent tubes to move the excess blow by out of the engine area which gives me a place to put after run oil back in that is effective as it is guided to where it is needed.

In both cases, after the oil has been put in turn the prop to circulate the oil. If possible try to store the plane so that the oil will go to the hardest bearing to lubricate with after run oil. On my older Saito's this was the front bearing but the newer stuff is nicer. With the 4 strokes, I put the oil in the vent tube and leave the container attached while I turn the prop 2 or 3 times. That keeps things clean on the outside and if it wants more oil, it is there.

YMMV

iskandar taib

My Feedback: (5)

Heh.. you should hear the advice people give for keeping F2D engines in good shape. It goes something like this. After flying, connect the clip, flip the engine to make sure it's dry. Then, model nose down, fill the muffler with gasoline, let it flow through the engine and come out the venturi. Put the plane in the rack, nose down, and let all the gasoline drip out. THEN lubricate liberally with after run oil of choice (I forget what the Russians use). Oh.. and don't forget to loosen that Nelson plug right after the last run, while the engine is still warm, or you might end up with a stuck plug (those are quite nasty). And don't forget to loosen all the mounting screws, or those nice Ukrainian motor mounts might crack during storage (happened to me.. argh..).

I don't like carrying bottles of gasoline in the car, or any in the garage, so I use spray carb cleaner instead. Seems to work. I used to use pump diesel fuel but it does make the engine hard to start the first run the next time. In Western Europe, they sell bottles of stuff called (in Holland) "Wasbenzin" in convenience stores, not exactly sure what it is but it's meant for cleaning, and I suspect this is what they use.

SOME racing pilots (and some Combat pilots too) like totally disassembling engines and cleaning them out after contests, to be honest, I think it does more harm than good - especially it it's a custom job from an engine rebuilder. Some of them, in their instructions, say "don't disassemble".

Iskandar

1QwkSport2.5r

It seems, based on the thread title that regular MMO is not the item to use in this case, but rather the MM Air tool oil version. So can we put the subject to bed yet? Among the Marvel products, the Air Tool Oil is what you would use IF you use any sort of after run at all and IF it has to be Marvel brand.

Sport_Pilot

The best after run oil is a mix of synthetic glow oil and about 5% castor oil. Not enough castor to congeal sufficiently and it mix's with the moisture instead of floating on top of the moisture trapping it against the metal.

Petroleum oils should only be used for storage, and then only when you know the engine is dried out.

jessiej

Very interesting post, islander. Quite a it of effort maintaining an engine run for a few seconds at a time. Much like. A high performance drag racer.

Jess